JP2005326494A - Image microscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image microscope superior in operation performance by correcting focus shift in observation using invisible light such as infrared light. <P>SOLUTION: The image microscope focuses an observation object O with an objective lens 1. An arbitrary magnified image is obtained by a zoom optical system 2 having zoom lenses 3, 4 and 5. The image microscope is focused on CCD 16 converting the observation object from the zoom optical system 2 into an electric signal through a focusing lens 14. At least one of the focusing lens 14 and CCD 16 is moved to a direction of an optical axis 8 of the focusing lens 14 with a focusing position correction means. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image microscope including an image sensor that electronically images an observation object.

  For example, a medical stereomicroscope (surgical microscope) used in a surgical operation is known as an image microscope that includes an imaging device that electronically images an observed object and magnifies the observed object. The medical stereomicroscope includes an illumination light source, an illumination optical system, an observation optical system having two main optical paths, an eyepiece, and the like. This type of medical stereomicroscope projects illumination light from an illumination light source onto an observation object via an illumination optical system, and displays an image to be observed by reflected light from the observation object in two main optical paths of the observation optical system. It is comprised so that it may guide to an eyepiece lens via. Therefore, by using this medical stereomicroscope, the surgeon can observe the observation position (for example, the surgical site) with binocular eyes.

  By the way, in recent treatment methods, infrared light or light in the vicinity of a wavelength of 400 nm or 700 nm, that is, light in a wavelength range where the sensitivity of the human eye is relatively low or insensitive (hereinafter these are collectively referred to). The use of invisible light is increasing. For example, in brain surgery, a surgical procedure for removing a malignant tumor may be performed by utilizing the property that a fluorescent substance selectively remains in cancer cells. Moreover, in ophthalmology, in order to suppress the progress of retinal detachment, a deep layer photocoagulation operation may be performed using infrared laser light. From such a background, a plurality of electronic imaging means having different wavelength sensitivities are provided, and the observation object position can be electronically observed in accordance with each wavelength regardless of whether visible light or invisible light is used. A medical stereomicroscope has been proposed (see, for example, Patent Document 1).

On the other hand, as a medical stereomicroscope, in order to improve the optical performance of visible light, a microscope that is configured to suppress optical performance deterioration due to the wavelength characteristic of light has been proposed. As such a medical stereomicroscope, in order from the side farthest from the object, a first lens group having a positive refractive power, a second lens group including at least one three-compound lens, and a positive refractive power A lens having an objective lens having a third lens group is known. By doing so, it is said that it is possible to reduce the difference between the distortion of the image seen with the left eye and the distortion of the image seen with the right eye, that is, the absolute amount of distortion. (For example, refer to Patent Document 2).
JP 5-344997 (paragraphs 0002 to 0030, FIG. 1) JP 2001-147378 A (paragraphs 0005 to 0031, FIGS. 1 to 3)

  However, the technique described in Patent Document 1 has a problem in that an optical axis shift (focal shift) of an imaging position due to wavelength characteristics easily occurs in an observation state using invisible light. In particular, in the technique described in Patent Document 1, since the zoom defocusing accompanying the zoom imaging operation is large, it is necessary to perform a focus operation that moves the entire microscope each time the zoom operation is performed. Therefore, the operation time is increased and the burden on the operator who is also an operator of the stereomicroscope is large.

  In general, in designing a lens, when optical performance in light in a predetermined wavelength region is improved, optical performance in light in other wavelength regions tends to deteriorate. Therefore, when a structure that improves optical performance in visible light as in the technique described in Patent Document 2, it is difficult to ensure optical performance in invisible light such as infrared light. Accordingly, the stereomicroscope described in Patent Document 2 also performs a focus operation that moves the entire microscope every time the zoom operation is performed in the observation state using invisible light, similarly to the stereomicroscope described in Patent Document 1. There is a need.

  The present invention has been made based on such circumstances, and can correct a focus shift even during observation using invisible light such as infrared light, and has good operation performance. An object is to provide an image microscope.

  An image microscope according to one embodiment of the present invention combines an objective lens for focusing on an observation object, a zoom optical system having a zoom lens for obtaining an arbitrary magnified image, and an observation image from the zoom optical system. An imaging lens for imaging, an imaging means having an imaging device for converting an observation image formed through the imaging lens into an electrical signal, and at least one of the imaging lens and the imaging device as the imaging lens Imaging position correction means for enabling movement in the optical axis direction.

  According to an image microscope according to an aspect of the present invention, when performing a zoom operation to obtain an enlarged image formed by arbitrarily magnifying an image of an observation object in both observation with visible light and observation with invisible light. Even if the focal position of the imaging lens is shifted in the optical axis direction with respect to the imaging device, the imaging position correcting means moves at least one of the imaging lens and the imaging device in the optical axis direction of the imaging lens, Can be combined. Therefore, the focus position by the imaging lens can be easily adjusted to the image sensor without performing a focus operation that moves the entire microscope.

  According to the embodiment of the present invention described above, an image microscope can be obtained that can correct a focus shift even during observation using invisible light such as infrared light, and has good operation performance.

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.
The image microscope of this embodiment includes a microscope unit 20 as shown in FIG. The microscope unit 20 includes an objective lens 1, a zoom optical system 2, an imaging lens 14, a TV camera head 15 as an imaging unit, an imaging position correction unit, and the like. In the microscope unit 20, from the observation object O side, along the optical axis 8 direction of the imaging lens 14 (same as the objective optical axis direction), the objective lens 1, the zoom optical system 2, the imaging lens 14, and the TV camera head. They are arranged in the order of 15.

  The objective lens 1 is for focusing on the observation object O. The zoom optical system 2 includes a first group fixed lens 3, a second group moving lens 4, and a third group moving lens 5 as a plurality of zoom lenses. The second group and third group moving lenses 4 and 5 are held on the moving lens frames 6 and 7 by adhesion or the like, respectively. The movable lens frames 6 and 7 can be moved by moving means. The moving means includes, for example, a guide shaft 9 as a guide mechanism, a rotatable cam 10, and a motor 13. The cam 10 is provided with two cam grooves 11 and 12. The cam grooves 11 and 12 are formed in a spiral shape or a part of a spiral that turns in different directions. The cam 10 is rotatably held by a motor 13.

  A guide shaft 9 disposed parallel to the optical axis 8 passes through one end of each moving lens frame 6, 7. Engaging protrusions 6a and 7a are provided on the peripheral surfaces of the movable lens frames 6 and 7, respectively.

  Therefore, when the motor 13 is driven and the cam 10 is rotated, the engagement protrusions 6a and 7a move along the cam grooves 11 and 12, respectively. That is, the movable lens frames 6 and 7 move in the direction of the optical axis 8 as the cam 10 rotates together with the second and third group moving lenses 4 and 5 while being guided by the guide shaft 9. At this time, since the cam grooves 11 and 12 are formed in a spiral shape or a part of a spiral that turns in different directions, the moving lens frame 6 and the moving lens frame 7 (the second group moving lens 4 and the third group). The moving lens 5) moves in synchronism with the direction in which the distance between them changes (the direction toward or away from each other). The moving means is not limited to this.

  The imaging lens 14 is for forming an observation image from the zoom optical system 2. The TV camera head 15 has a CCD 16 as an image sensor. The TV camera head 15 is connected to a monitor (not shown). An observation image from the zoom optical system 2 is formed on the CCD surface 16 a of the CCD 16 through the imaging lens 14.

  The TV camera head 15 is held by a holding member 17. The guide shaft 9 passes through the holding member 17. The holding member 17 is engaged with the lead screw 18. A manual knob 19 is provided on the lead screw 18.

  Therefore, by holding the manual knob 19 and rotating the lead screw 18, the holding member 17 moves in the direction of the optical axis 8 while being guided by the guide shaft 9. That is, the CCD 16 moves in the direction of the optical axis 8 as the lead screw 18 is rotated.

  In other words, in the image microscope of the present embodiment, the imaging position correcting means moves the imaging lens 14 in the direction of the optical axis 8 and includes a guide shaft 9, a lead screw 19, a manual knob 19, and the like. It is configured. The guide shaft 9 is a part of the moving means for moving the movable lens frames 6 and 7 and is also a part of the imaging position correcting means.

  In FIG. 1, the lead screw 19 is a left-hand screw, but the lead screw 19 may be a right-hand screw. As the lead screw 19, one of a left screw and a right screw, for example, a screw whose rotational direction of the screw and the moving direction of the holding member 17 are not sensibly contradicted when viewed from the operator operating the image microscope is used. Can be used.

  The image microscope of this embodiment is used as follows.

  When performing visible light observation, the following is performed. First, a light source (not shown) capable of emitting visible light is prepared. The light source is turned on, and the observation object O is irradiated with visible light. The microscope unit 20 is moved to align the observation object O with the focal position of the objective lens 1 (so-called focusing is performed). A visible light beam (reflected light from the observation object) from the observation object O passes through the objective lens 1, is zoomed by the zoom optical system 2, and forms an optical image on the CCD surface 16 a of the CCD 16 by the imaging lens 14. Through the above operation, the observer (user of the image microscope) can observe the observation image of the observation object O with visible light via the monitor connected to the TV camera head 15.

  Further, when it is desired to change the magnification of the optical image connected to the CCD surface 16a, the motor 13 is driven to rotate the cam 10 by a predetermined amount, and the moving lens frame 6, so that the distance between them changes. 7 may be moved along the guide axis 9 in parallel with the optical axis 8.

  In the image microscope of the present embodiment, the visible light that has been scaled by the zoom optical system 2 through the objective lens 1 is configured to always form an optical image on the CCD surface 16a by the imaging lens 14. Therefore, even if the moving lens frames 6 and 7 holding the second group and third group moving lenses 4 and 5 are moved along the optical axis 8 so that the distance between them changes, the focus is substantially reduced. There is no deviation. Therefore, by simply rotating the cam 10, the magnification of the optical image connected to the CCD surface 16a by the imaging lens 14 can be changed to an arbitrary magnification.

  On the other hand, when the observation object is a blood vessel or the like directly under the body surface, the observation object is irradiated with infrared light, and the reflected light from the observation object is observed. When invisible light observation is performed using invisible light such as infrared light, the following is performed. A light source capable of emitting invisible light having a desired wavelength is prepared. In this embodiment, a light source capable of emitting infrared light is used. Also in this case, similarly to the observation using visible light, the observation object O is irradiated with infrared light emitted from the light source, and the microscope unit 20 is moved so that the observation object O is aligned with the focal position of the objective lens 1. An infrared light beam from the observation object O (infrared reflected light from the observation object) is incident on the CCD 16 through the objective lens 1, the zoom optical system 2, and the imaging lens 14.

  By the way, since infrared light has a wavelength different from that of visible light, the refractive index of the lens is also different from that of visible light. Therefore, when infrared light is used, the image forming point by the image forming lens 14 is shifted in the direction of the optical axis 8 with respect to the CCD surface 16a of the CCD 16. In the image microscope of the present embodiment, the manual knob 19 may be rotated by a predetermined amount in order to correct the optical axis deviation. As a result, the lead screw 18 rotates and the holding member 17 engaged with the lead screw 18 moves along the guide shaft 9 in the direction of the optical axis 8. The observer may adjust the imaging point by the imaging lens 14 to the CCD surface 16 a of the CCD 16 by rotating the lead screw 18 while observing the monitor connected to the TV camera head 15. With the above operation, the observation image of the observation object O by infrared light can be observed through the monitor connected to the TV camera head 15.

  The image microscope according to the present embodiment includes the zoom optical system 2 for enlarging and reducing the observation image. However, the same phenomenon occurs even when the zoom optical system 2 is not included. That is, when infrared light is incident on the CCD 16 via the objective lens 1 and the imaging lens 14, the refractive index is different from that of visible light. The point deviates in the direction of the optical axis 8 with respect to the CCD surface 16a of the CCD 16. Even if the zoom optical system 2 is not included at this time, the manual knob 19 may be rotated by a predetermined amount in order to correct the optical axis deviation. As a result, the lead screw 18 rotates and the holding member 17 engaged with the lead screw 18 moves along the guide shaft 9 in the direction of the optical axis 8. The observer may adjust the imaging point by the imaging lens 14 to the CCD surface 16 a of the CCD 16 by rotating the lead screw 18 while observing the monitor connected to the TV camera head 15. With the above operation, the observation image of the observation object O by infrared light can be observed through the monitor connected to the TV camera head 15.

  With reference to FIG. 2, the movement amounts of the zoom optical system 2, the imaging lens 14, and the CCD 16 of the TV camera head 15 required in response to the zooming operation will be described.

  As described above, the imaging position at the time of visible light observation is always the point P (intersection of the optical axis 8 and the CCD surface 16a). This does not change even when a zooming operation (movement of the second group and third group moving lenses 4 and 5 accompanying rotation of the cam 10) is performed. That is, it is not necessary to move the zoom optical system 2, the imaging lens 14, or the CCD 16 of the TV camera head 15 with the zooming operation.

On the other hand, when invisible light observation such as infrared light observation is performed when the second group and third group moving lenses 4 and 5 of the zoom optical system 2 are provided at positions indicated by solid lines, the imaging lens 14 invisible light passing through the ends up focused on the point P _1. In this case, it is necessary to move the CCD 16 along with the TV camera head 15 in the direction away from the observation object O by the distance b. In this way, invisible light that has passed through the imaging lens 14 can be imaged on the CCD surface 16a. Next, the zooming operation, and moves each movable lens 4,5 distance d (moves to the position shown by the two-dot chain line), the invisible light passing through the imaging lens 14, the point P ₂ It will form an image. In this case, the CCD 16 needs to be further moved away from the observation object O together with the TV camera head 15 by the distance c. In this way, invisible light that has passed through the imaging lens 14 can be imaged on the CCD surface 16a.

  Here, the zoom optical system 2 used in the present embodiment can continuously change the magnification. However, even if the zoom optical system 2 can change the magnification stepwise, for example, the turret magnification can be changed. By doubling, the imaging position is shifted in the same manner as in the structure including the zoom optical system 2. In this case as well, invisible light that has passed through the imaging lens 14 can be imaged on the CCD surface 16a by moving the CCD 16 together with the TV camera head 15 in a direction away from the observation object O.

  As described above, the image microscope according to the present embodiment includes at least one of the imaging lens 14 and the CCD 16, for example, an imaging position correction unit that enables the CCD 16 to move in the direction of the optical axis 8. Therefore, even when switching from visible light observation to invisible light observation such as infrared light observation, invisible light that has passed through the imaging lens 14 can be imaged on the CCD surface 16a. In addition, at this time, at least one of the imaging lens 14 and the CCD 16, for example, the CCD 16 may be moved together with the TV camera head 15, and the microscope unit 20 itself may not be moved for the focus operation.

  Therefore, according to the image microscope of the present embodiment, it is possible to correct a focus shift even during observation using invisible light such as infrared light, and it is possible to obtain an image microscope with good operation performance. .

  Further, according to the image microscope of the present embodiment, the moving means for moving the second group and third group moving lenses 4 and 5 is provided in parallel with the direction of the optical axis 8 of the imaging lens 14, and the second group and A guide shaft 9 is provided for guiding the third group moving lenses 4 and 5 along the direction of the optical axis 8. Therefore, the second group and third group moving lenses 4 and 5 can be moved in a stable state along the direction of the optical axis 8.

  In the image microscope of the present embodiment, the imaging position correcting means moves the imaging lens 14 in the direction of the optical axis 8, but the imaging position correcting means uses the CCD 16 as an imaging device as the optical axis 8. It may be moved in the direction. Further, the imaging position correcting means may move both the imaging lens 14 and the CCD 16 in the direction of the optical axis 8 so that the distance between the imaging lens 14 and the CCD 16 changes.

Hereinafter, a second embodiment of the present invention will be described with reference to FIGS.
The image microscope of the present embodiment is a stereomicroscope (medical stereomicroscope) that can be suitably used for, for example, surgery, and has two optical paths corresponding to the left and right eyes.

The image microscope of this embodiment includes a microscope unit 20 as shown in FIG. The microscope unit 20 includes an objective lens 1, a pair of zoom optical systems 2L and 2R, two pairs (four) of imaging lenses 14L ₁ , 14R ₁ , 14L ₂ and 14R ₂ , and two pairs (four) as imaging means. TV camera heads 15L ₁ , 15R ₁ , 15L ₂ , 15R ₂ , imaging position correcting means having interlocking means, a pair of dichroic prisms 22L, 22R, and the like.

The image microscope forms an observation image on the CCDs 16L ₂ and 16R ₂ of the TV camera heads 15L ₂ and 15R ₂ by the imaging lenses 14L ₂ and 14R ₂ when observing visible light, and the imaging lens when observing infrared light. 14L _1, the 14R ₁ is configured to image the observation image in CCD16L _1, 16R ₁ of the TV camera head _{15L 1,} 15R 1.

  The objective lens 1 is for focusing on the observation object. The pair of left and right zoom optical systems 2L and 2R are configured similarly to the zoom optical system 2 provided in the image microscope of the first embodiment. In other words, the zoom optical systems 2L and 2R have first group fixed lenses 3L and 3R, second group moving lenses 4L and 4R, and third group moving lenses 5L and 5R, respectively, as a plurality of zoom lenses. . The second group moving lens 4L of the zoom optical system 2L and the second group moving lens 4R of the zoom optical system 2R are held on the moving lens frame 6 by bonding or the like. The third group moving lens 5L of the zoom optical system 2L and the third group moving lens 5R of the zoom optical system 2R are respectively held on the moving lens frame 7 by bonding or the like. These moving lens frames 6 and 7 can be moved by moving means.

The moving means includes, for example, a guide shaft 9 as a guide mechanism, a rotatable cam 10, and a motor 13. The cam 10 is provided with three cam grooves 11, 12, and 21. The cam grooves 11 and 12 are formed in a spiral shape or a part of a spiral that turns in different directions. The cam 10 is rotatably held by a motor 13. A guide shaft 9 disposed parallel to the objective optical axis 28 passes through each moving lens frame 6, 7. Incidentally, the objective optical axis 28, the optical axis of the imaging lens 14L _1, and the optical axis of the imaging lens 14R ₁ are parallel to each other. Engaging protrusions 6a and 7a are provided on the peripheral surfaces of the movable lens frames 6 and 7, respectively. The engaging protrusions 6a and 7a are engaged with cam grooves 11 and 12 provided in the cam 10, respectively.

  Therefore, when the motor 13 is driven and the cam 10 is rotated, the engagement protrusions 6a and 7a move along the cam grooves 11 and 12, respectively. That is, the moving lens frames 6 and 7 are moved in the direction of the optical axis 8 ′ as the cam 10 rotates while being guided by the guide shaft 9. The moving lens frame 6 and the moving lens frame 7 move in synchronization with the direction in which the distance between them changes.

Each of the TV camera heads 15L ₁ , 15R ₁ , 15L ₂ , 15R ₂ is configured in the same manner as the TV camera head 15 provided in the image microscope of the first embodiment. Imaging lens 14L ₁ images the observation image by the infrared light from the zoom optical system 2L to CCD16L ₁ of the TV camera head 15L _1. Imaging lens 14R ₁ images the observation image by the infrared light from the zoom optical system 2R to CCD16R ₁ of the TV camera head 15R _1. Imaging lens 14L ₂ images the visible light observation image from the zoom optical system 2L to CCD16L ₂ of the TV camera head 15L _2. Imaging lens 14R ₂ images the visible light observation image from the zoom optical system 2R to CCD16R ₂ of the TV camera head 15R _2.

The image forming position correcting means zooms the optical systems 2L and 2R so that the image forming lenses 14L ₁ and 14R ₁ can always focus on the CCDs 16L ₁ and 16R ₁ of the TV camera heads 15L ₁ and 15R _1. In association with the zooming operation, the imaging lens 14L ₁ , 14R ₁ and at least _one of the CCD camera 16L ₁ , 16R ₁ of the TV camera head 15L ₁ , 15R ₁ , for example, the imaging lens 14L ₁ , 14R ₁ are interlocked. have.

Specifically, the imaging lenses 14L ₁ and 14R ₁ are held by the holding member 27. The guide shaft 9 disposed parallel to the objective optical axis 28 passes through the holding member 27. Further, an engagement protrusion 27 a is provided on the peripheral surface of the holding member 27. The engagement protrusion 27 a is engaged with the cam groove 21 provided in the cam 10.

That is, when the motor 13 is driven and the cam 10 is rotated, the engagement protrusion 27 a moves along the cam groove 21. That is, the holding member 27 moves in the direction of the objective optical axis 28 as the cam 10 rotates together with the imaging lenses 14L ₁ and 14R ₁ while being guided by the guide shaft 9. The cam groove 21 is arranged so that the holding member 27 moves in a direction approaching the moving lens frame 7 when the cam 10 rotates in a direction to reduce the distance between the moving lens frame 6 and the moving lens frame 7. Is formed.

The dichroic prisms 22L and 22R have characteristics of transmitting infrared light and reflecting visible light. The dichroic prisms 22L and 22R are provided between the third group moving lenses 5L and 5R of the zoom optical systems 2L and 2R and the imaging lenses 14L ₁ and 14R ₁ , respectively. The dichroic prisms 22L and 22R transmit the infrared light emitted from the third group moving lenses 5L and 5R of the zoom optical systems 2L and 2R, respectively, and enter the imaging lenses 14L ₁ and 14R ₁ . Further, the dichroic prisms 22L and 22R reflect visible light emitted from the third group moving lenses 5L and 5R of the zoom optical systems 2L and 2R, and enter the imaging lenses 14L ₂ and 14R ₂ .

  The image microscope of the present embodiment is used as follows.

  A first light source (not shown) capable of emitting visible light and a second light source (not shown) capable of emitting infrared light are prepared. The first and second light sources are turned on, and the observation object O is irradiated with visible light and infrared light simultaneously. Visible light observation and infrared light observation are performed by switching the image input of the monitor.

When the image input is a visible light observation, it is as follows. Reflected light (visible light beam) from the observation object O passes through the objective lens 1, is zoomed by the zoom optical systems 2L and 2R, is reflected by the dichroic prisms 22L and 22R, and is reflected by the imaging lenses 14L ₂ and 14R _2. Optical images are formed on the CCD surfaces 16a _L2 and 16a _R2 of the CCDs 16L ₂ and 16R ₂ of the camera heads 15L ₂ and 15R ₂ , respectively.

In order to change the magnification of the obtained optical image, the motor 13 is driven to rotate the cam 10 by a predetermined amount, and the movable lens frames 6 and 7 are moved to the guide shaft 9 so that the distance between them changes. And may be moved in parallel with the objective optical axis. In the image microscope of the present embodiment, as in the image microscope of the first embodiment, the visible light that has been scaled by the zoom optical systems 2L and 2R is always transmitted by the imaging lenses 14L ₂ and 14R ₂ through the objective lens 1. An optical image is formed on the CCD surfaces 16a _L2 and 16a _R2 of the TV camera heads 15L ₂ and 15R ₂ . Therefore, even if the movable lens frames 6 and 7 are moved along the optical axis 8 ′, the focus is not substantially shifted. Therefore, by simply rotating the cam 10, the magnification of the optical image connected to the CCD surfaces 16a _L2 and 16a _R2 of the TV camera heads 15L ₂ and 15R ₂ can be changed to an arbitrary magnification by 14L ₂ and 14R ₂ .

On the other hand, when the image input is an infrared light observation, it is as follows. The infrared light beam from the observation object O passes through the objective lens 1, is zoomed by the zoom optical systems 2L and 2R, passes through the dichroic prisms 22L and 22R, and further passes through the imaging lenses 14L ₁ and 14R ₁ to the TV. The light enters the CCDs 16L ₁ and 16R ₁ of the camera heads 15L ₁ and 15R ₁ . However, when infrared light is used, the image forming point by the image forming lenses 14L ₁ and 14R ₁ becomes the objective optical axis with respect to the CCD surfaces 16a _L1 and 16a _R1 of the CCD cameras 16L ₁ and 16R ₁ of the TV camera heads 15L ₁ and 15R _1. Deviation in 28 directions.

Here, referring to FIG. 4, the zoom optical systems 2L and 2R, the imaging lenses 14L ₁ and 14R ₁ , and the CCD cameras 16L ₁ and 16R of the TV camera heads 15L ₁ and 15R ₁ associated with the zooming operation in the infrared light observation. The positional relationship of ₁ will be described.

The deviation of the imaging point of the imaging lenses 14L ₁ , 14R _{1 in} the direction of the objective optical axis 28 is relative to the positions of the second group and third group moving lenses 4L, 4R, 5L, 5R of the zoom optical systems 2L, 2R. It is determined uniquely. Therefore, a predetermined relationship is established between the moving distances of the second and third group moving lenses 4L, 4R, 5L, and 5R of the zoom optical systems 2L and 2R and the moving distances of the imaging lenses 14L ₁ and 14R _1. As described above, the imaging lenses 14L ₁ and 14R ₁ are interlocked with the movement of the moving lenses 4L, 4R, 5L, and 5R, so that the imaging points of the imaging lenses 14L ₁ and 14R ₁ are always set to the imaging lenses 14L ₁ , 14L ₁ , It is possible to overlap the intersection of the optical axis of 14R ₁ and the CCD surfaces 16a _L1 and 16a _R1 of the CCDs 16L ₁ and 16R ₁ of the TV camera heads 15L ₁ and 15R ₁ .

In this image microscope, as shown in FIG. 4, the imaging position at the time of infrared light observation is always at points Q1 and Q2 (the optical axes of the imaging lenses 14L ₁ and 14R ₁ and the CCD 16L of the TV camera heads 15L ₁ and 15R ₁ . The cam grooves 21 of the cam 10 are formed so as to be the intersection points of the CCD surfaces 16a _L1 and 16a _{R1 of 1} and 16R ₁ .

Therefore, zooming operation of the zoom optical systems 2L, 2R (moving lenses 4L, 4R, 5L, 5R accompanying the rotation of the cam 10) is performed, and each moving lens 4L, 4R, 5L, 5R is pointed from the position of the solid line. When moving to the position of the chain line by the distance e (each moving lens 4L, 4R and each moving lens 5L, 5R approaches twice the distance e), the imaging lenses 14L ₁ , 14R ₁ also change from the solid line to the one-dot chain line. It moves to the position by the distance f (to the TV camera heads 15L ₁ and 15R ₁ or the dichroic prisms 22L and 22R side), and the imaging position coincides with the points Q1 and Q2. By doing so, the infrared light scaled by the zoom optical systems 2L and 2R is converted into the CCD surface 16a of the CCDs 16L ₁ and 16R ₁ of the TV camera heads 15L ₁ and 15R ₁ by the imaging lenses 14L ₁ and 14R ₁ . _Images can always be formed on _L1 and 16a _R1 .

  As described above, according to the image microscope of the present embodiment, as in the first embodiment, it is possible to correct a focus shift even during observation using invisible light such as infrared light, An image microscope with good operation performance can be obtained.

Moreover, the imaging position correction means always focuses the imaging lenses 14L ₁ and 14R ₁ on the CCD surfaces 16a _L1 and 16a _R1 of the CCD cameras 16L ₁ and 16R ₁ of the TV camera heads 15L ₁ and 15R _1. Along with the zooming operation of the zoom optical systems 2L and 2R, at least one of the imaging lenses 14L ₁ and 14R ₁ and the CCD cameras 16L ₁ and 16R ₁ of the TV camera heads 15L ₁ and 15R ₁ , for example, the imaging lens 14L ₁ , 14R ₁ are interlocked. Therefore, even when switching from visible light observation to infrared light observation, it is not necessary to perform troublesome focusing each time. Therefore, a good visible light observation image and an invisible light observation image such as an infrared light observation image can be obtained only by switching the image input.

Furthermore, according to the image microscope of the present embodiment, a rotatable cam 10 is used as a moving means for moving the second group and third group moving lenses 4L, 4R, 5L, 5R of the zoom optical systems 2L, 2R. In addition, a cam groove 21 provided in the cam 10 is used as interlocking means. Therefore, the imaging lenses 14L ₁ and 14R ₁ can be interlocked with the zooming operation with a simple configuration without adding new parts.

In the image microscope of the present embodiment, the imaging position correction means moves the imaging lenses 14L ₁ and 14R ₁ in the direction of the objective optical axis 28, but the imaging position correction means serves as an image sensor. The CCDs 16L ₁ and 16R ₁ may be moved in the direction of the objective optical axis 28. Also, imaging position correction means, the distance between the CCD16R ₁ distance and the imaging lens 14R ₁ and the TV camera head 15R ₁ between CCD16L ₁ imaging lens 14L ₁ and the TV camera head 15L ₁ is synchronized Thus, both the imaging lenses 14L ₁ and R ₁ and the CCDs 16L ₁ and 16R ₁ may be moved in the direction of the objective optical axis 28 so as to change.

Hereinafter, a third embodiment of the present invention will be described with reference to FIG.
The interlocking means provided in the image microscope of the present embodiment includes a zoom lens position detecting means for detecting the positions of the second group and third group moving lenses 4L, 4R, 5L, and 5R of the zoom optical systems 2L and 2R, and the zoom lens. together with the position information from the position detecting means is inputted, the image forming lens _14L 1, 14R ₁ and at least one of CCD16L _1, 16R ₁ of the TV camera head _15L 1, 15R _1, for example, an imaging lens _14L 1, 14R ₁ And a control box 38 as a control means for outputting the amount of movement. The control box 38 has at least one of the imaging lenses 14L ₁ , 14R ₁ and the CCD cameras 16L ₁ , 16R ₁ of the TV camera heads 15L ₁ , 15R ₁ according to the selection of the wavelength characteristics of the light to be used, For example, it is selected whether or not the imaging lenses 14L ₁ and 14R ₁ are interlocked with the movement of the second group and third group moving lenses 4L, 4R, 5L, and 5R of the zoom optical systems 2L and 2R. .

  Specifically, the zoom lens position detection unit has an encoder 33. The encoder 33 is provided in the motor 13 that holds the cam 10 rotatably. The encoder 33 is electrically connected to the control box 38. The rotation amount of the motor 13 detected by the encoder 33, that is, the position information of the second group and the third group moving lenses 4L, 4R, 5L, 5R of the zoom optical systems 2L, 2R is input to the control box 38.

The holding member 27 that holds the imaging lenses 14L ₁ and 14R ₁ is independent of the cam 10 and is engaged with a lead screw 31 connected to the stepping motor 32. The stepping motor 32 is electrically connected to the control box 38. The operation amount of the stepping motor 32 is determined by position information of the second group and the third group moving lenses 4L, 4R, 5L, and 5R of the zoom optical systems 2L and 2R obtained by the encoder 33.

  The observation object O is illuminated with illumination lens optical systems 34 and 35, a light guide 36, and a light source 37. The light source 37 has a switching mechanism capable of selectively irradiating visible light and infrared light as invisible light. The switching mechanism of the light source 37 is electrically connected to the control box 38. Depending on the information input from the switching mechanism, the control box 38 makes the imaging lens interlock or not interlock with the second group and the third group moving lenses 4L, 4R, 5L, and 5R of the zoom optical systems 2L and 2R. Select. Since the other configuration is the same as that of the above-described second embodiment, the overlapping description is omitted by attaching the same reference numerals to the drawings.

  The image microscope of this embodiment is used as follows.

The observer selects visible light observation or infrared light observation and switches the switching mechanism of the light source 37 as desired. First, a case where visible light observation is selected will be described. In the case of visible light observation, the observation images from the zoom optical systems 2L and 2R are always displayed on the TV camera head by the imaging lenses 14L ₂ and 14R ₂ even when the zooming operation is performed as in the image microscope of the second embodiment. The images are formed on the CCD surfaces 16a _L2 and 16a _R2 of the CCDs 16L ₂ and 16R ₂ of 15L ₂ and 15R ₂ . Therefore, when visible light observation is selected, the control box 38 causes the interlocking means to move the imaging lenses 14L ₂ and 14R ₂ to the second group of the zoom optical systems 2L and 2R and the third group moving lenses 4L, 4R, 5L and 5R. Make selections that are not linked to movement. At this time, the control box 38 does not send a rotation signal to the stepping motor 32.

Next, a case where infrared light observation is selected will be described. When infrared light is used, the observation images from the zoom optical systems 2L and 2R are displaced in the direction of the optical axis 8 ′ from the CCD surfaces 16a _L1 and 16a _R1 of the CCDs 16L ₁ and 16R ₁ of the TV camera heads 15L ₁ and 15R ₁ . The image is formed at the position. Therefore, when infrared light observation is selected, the control box 38 causes the interlocking means to change the imaging lenses 14L ₁ and 14R ₁ into the second group and the third group moving lenses 4L, 4R, 5L, and 5R of the zoom optical systems 2L and 2R. Select to be linked to the movement of

The amount of rotation of the cam 10 is detected by the encoder 33, and position information of the second group and third group moving lenses 4L, 4R, 5L, 5R of the zoom optical systems 2L, 2R is obtained. Position information of the second and third group moving lenses 4L, 4R, 5L, and 5R obtained by the encoder 33 is transmitted to the control box 38. Deviations in the optical axis 8 direction of the imaging points of the imaging lenses 14L ₁ , 14R ₁ with respect to the positions of the second group and third group moving lenses 4L, 4R, 5L, 5R of the respective zoom optical systems 2L, 2R. Since it is uniquely determined, the control box 38 operates the stepping motor 32 based on the information input from the encoder 33 to rotate the lead screw 32 by a predetermined number of rotations. Thereby, the imaging points of the imaging lenses 14L ₁ and 14R ₁ can be set on the CCD surfaces 16a _L1 and 16a _R1 of the CCDs 16L ₁ and 16R ₁ of the TV camera heads 15L ₁ and 15R ₁ .

Further, according to the interlocking means, always zoom optical system even if the scaling operation 2L, an observation image of 2R in the TV camera head _{15L 1,} CCD16L 1 of 15R _1, 16R ₁ of CCD surface _16a L1, _{16a R2} An image can be formed. Further, by performing communication among the encoder 33, the control box 38, and the stepping motor 32 in real time, it is possible to suppress out-of-focus caused by shifting the focal positions of the imaging lenses 14L ₁ and 14R ₁ .

As described above, according to the image microscope of the present embodiment, as in the second embodiment, it is possible to correct a focus shift during observation using invisible light such as infrared light, and An image microscope with good operation performance can be obtained. Moreover, according to the image microscope of the present embodiment, the imaging lenses 14L ₂ and 14R ₂ , the TV camera heads 15L ₂ and 15R ₂ , and the dichroic prisms 22L and 22R can be omitted. Therefore, the image microscope can be reduced in size and operability can be improved.

The interlocking means includes an encoder 33 that detects the positions of the second and third group moving lenses 4L, 4R, 5L, and 5R of the zoom optical systems 2L and 2R, and the moving lenses 4L and 4R obtained by the encoder. A control box 38 for inputting the positional information and outputting the movement amounts of the imaging lenses 14L ₁ and 14R ₁ is provided. Therefore, the light at the imaging point of the imaging lenses 14L ₁ and 14R ₁ that is uniquely determined with respect to the positions of the second group and third group moving lenses 4L, 4R, 5L, and 5R of the zoom optical systems 2L and 2R. The deviation in the direction of the axis 8 can be automatically corrected.

In addition, in the control box 38, the interlocking unit moves the imaging lenses 14L ₁ and 14R ₁ into the second group and the third group moving lens 4L of the zoom optical systems 2L and 2R according to the selection of the wavelength characteristics of the light to be used. Select whether to interlock with the movement of 4R, 5L, 5R. Therefore, the observer can easily obtain a non-visible light observation image such as a good visible light observation image and an infrared light observation image only by switching the switching mechanism of the light source 37.

  When performing a surgical operation, the surgeon and the surgical assistant usually perform the operation jointly. Therefore, the surgical assistant also needs to be able to observe the observation position as an observation object in the same manner as the surgeon. . Therefore, when the first to third image microscopes are used as a medical stereomicroscope, a sub-observation optical system that branches off from the middle of the optical path is provided, and an observer (for example, a surgical operation microscope) is provided via the sub-observation optical system. A third person (for example, a surgical assistant) other than the surgeon may observe the observation object in the same manner as the operator.

  According to each of the embodiments, the following configuration is obtained.

(Appendix 1)
A zoom optical system having a plurality of zoom lenses for obtaining an enlarged image obtained by arbitrarily enlarging an image of an observation object;
An imaging lens for forming an observation image from the zoom optical system;
An imaging means having an imaging element for converting an observation image formed through the imaging lens into an electrical signal;
An imaging position correction unit that enables movement of at least one of the imaging lens and the imaging element in an optical axis direction of the imaging lens;
An image microscope comprising:

(Appendix 2)
The imaging position correcting means includes
Interlocking means for interlocking at least one of the imaging lens and the image sensor with a zooming operation of the zoom optical system so that the focal point of the imaging lens can always form an image on the image sensor. The image microscope according to appendix 1, wherein:

(Appendix 3)
A movable cam having a rotatable cam and moving at least one zoom lens in a direction parallel to the optical axis direction of the imaging lens;
The image microscope according to claim 2, wherein the interlocking means has a cam groove provided in the cam.

(Appendix 4)
The image according to claim 3, wherein the moving unit includes a guide mechanism that is provided in parallel with the optical axis direction of the imaging lens and guides the zoom lens along the optical axis direction. microscope.

(Appendix 5)
The interlocking means is
Zoom lens position detecting means for detecting the position of the zoom lens;
Control means for inputting position information of the zoom lens obtained by the zoom lens position detecting means and outputting a movement amount of at least one of the imaging lens and the image sensor;
The image microscope according to appendix 2, characterized by comprising:

(Appendix 6)
6. The image microscope according to claim 5, wherein the control unit selects the interlocking unit to link or disengage at least one of the imaging lens and the imaging element according to selection of wavelength characteristics of light to be used. .

1 is a side view showing a partial cross section of an image microscope according to a first embodiment of the present invention. FIG. 2 is a view for explaining movement of a zoom optical system, an imaging lens, and a CCD of a TV camera head accompanying a zooming operation of the image microscope of FIG. 1. The side view which shows the image microscope which concerns on the 2nd Embodiment of this invention in partial cross section. FIG. 4 is a diagram for explaining movement of a zoom lens system, an imaging lens, and a CCD of a TV camera head according to a magnification operation of the image microscope of FIG. 3. FIG. 6 is a side view showing a partial cross section of an image microscope according to a third embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Objective lens 2, 2L, 2R ... Zoom optical system 3, 3L, 3R ... 1st group fixed lens (zoom lens), 4, 4L, 4R ... 2nd group moving lens (zoom lens), 5, 5L , 5R ... third group movable lens (zoom lens), 8,8 '... optical axis, 9 ... guide shaft (guide mechanism), 10 ... cam, 11, 12, 21 ... cam groove, 14,14L _1, 14R ₁ , 14L ₂ , 14R ₂ ... Imaging lens, 15, 15L ₁ , 15R ₁ , 15L ₂ , 15R ₂ ... TV camera head (imaging means), 16, 16L ₁ , 16R ₁ , 16L ₂ , 16R ₂ , ... CCD ( Image sensor)

Claims (3)

An objective lens for focusing on the observation object;
An imaging lens for forming an observation image from the objective lens;
An imaging means having an imaging element for converting an observation image formed through the imaging lens into an electrical signal;
An imaging position correction unit that enables movement of at least one of the imaging lens and the imaging element in an optical axis direction of the imaging lens;
An image microscope comprising: An objective lens for focusing on the observation object;
A zoom optical system having a zoom lens for obtaining an arbitrary magnified image;
An imaging lens for forming an observation image from the zoom optical system;
An imaging means having an imaging element for converting an observation image formed through the imaging lens into an electrical signal;
An imaging position correction unit that enables movement of at least one of the imaging lens and the imaging element in an optical axis direction of the imaging lens;
An image microscope comprising: The imaging position correcting means includes
Interlocking means for interlocking at least one of the imaging lens and the image sensor with a zooming operation of the zoom optical system so that the focal point of the imaging lens can always form an image on the image sensor. The image microscope according to claim 1.

Images